防洪工程之成本效益與風險評估－以基隆河流域整治計畫為例

The Cost-Benefit Analysis and Risk Assessment of Public Projects: A Case Study of the Keelung River Basin Integrated Flood Control Plan

張靜貞(Ching-Cheng Chang) ； 蘇明道(Ming-Daw Su) ； 糠瑞林(Jui-Lin Kang) ； 許文科(Wen-Ko Hsu) ； 鄧慰先(Wei-Hsien Teng) ； 周磊(Lei Chou)

《臺灣經濟預測與政策》 37卷2期 (2007/03) Pp. 111-137

https://doi.org/10.29629/TEFP.200703.0004

摘要

有鑑於臺灣近年來颱風洪水災情的頻繁，區域水災防治工程計畫已經成為政府與民眾所共同關切之重大議題。本研究以「塞隆河整體治理計畫」為例，引進巨災保險業在分析保費時所使用的全或然率模型之概念，進行洪災損失之風險評估。評估方法除了利用國科會所研發之電腦模擬的淹水潛勢圖檔資料外，也透過各種社經與土地利用之地理資訊圖層資料庫之套疊，以及由實際調查資料建立受災之住宅區與工商業之淹水深度損失曲線，勾勒出完整的全年累計損失之超越機率分配圖，最後並利用風險決策理論雄導出之工程最適水率條件式，進行「塞隆河整體治理計畫」之成本效益評估，評估結果顯示在本研究的假設下，目前政府在塞隆河流域所規劃之防洪治理計畫具有相當的淨效益。

關鍵字

成本效益分析 ； 地理資訊系統 ； 累計損失超越機率 ； 全或然率模型

並列摘要

Due to the rising damages caused by recent typhoons and flooding events, regional flood control projects have become common concerns for the government and public. This paper introduces a fully probabilistic modeling technique into the flood loss assessment and cost-benefit analysis of flood control projects, using the Keelung River Basin Integrated Flood Control Plan as an example. Computer simulated flood hazard maps from the National Science Council were used in conjunction with the GIS-based census data and land uses information for the flood risk exposure analysis. The estimation of direct flood damages to residential and commercial buildings were based on the depth-damage functions established by previous surveys on the disaster areas. Furthermore, an aggregate loss exceedance probability curve was presented for a complete assessment on annual overall losses. Finally, a decision making theory under risk is used to derive the optimal investment level, aiming at improving the cost and benefit assessment of a flood control project. The methods and empirical results from a case study on the Keelung River Basin Integrated Flood Control Plan form a supporting basis for the existing flood management strategies by the government.

並列關鍵字

Cost-benefit analysis ； Geographic information system ； Aggregate loss exceedance probability ； Fully probabilistic model

參考文獻

Dasgupta, A. K.,D.W. Pearce(1972).Cost-Benefit Analysis.New York:Barnes and Noble.

Dong, W.(2001).Building a More Profitable Portfolio-Modern Portfolio Theory with Application to Catastrophe Insurance.London:Reactions Publishing Group.

Grossi, P.,H. Kunreuther(2005).Catastrophe Modeling: A New Approach to Managing Risk.New York:Springer Science.

Guy Carpenter and Company Website

Kates, R. W.(1965).Research Paper No. 98.Chicago, Illinois:University of Chicago, Department of Geography.